Viewing device



12, 1940. WOOD 2,193,016

VIEWING DEVICE Filed April 16, 1938 2 Sheets-Sheet l 68 .22 F i .1. 5 53 67 @2 13? f 5 M 54 2 hp... b 8 23 5' 25. 4'6 I so 15 I21 1/ 1 1a 24 96 91 i \W Donald L. Wood I NVEN TOR March 12, 1940.

D. L. WOOD VIEWING DEVICE Filed April 16, 1938 2- Sheets-Sheet '2 INVENTOR W. M BY A? A? ATToRN Donald L. Wood lrv Patented Mar. 12, 1940 UNITED STATES PATENT OFFICE 2,193,016 'vmwmo nEvIoE Application April 16, 1938, Serial No. 202,488 4 Claims. (c1.- 88-16) The present invention relates to a viewing device and more particularly to a viewing device which may be inserted into the magazine chamber of a photographic apparatus for finding 5 and/or focusing through the objective of the apparatus.

It is quite necessary in certain types of photographic work to obtain maximum sharpness of the image in the focal plane of the objective.

Such sharpness of focus may be obtained by accurate measurement of the distance between the photographic objective and the object and then setting the objective focus according to its calibrated scale. However, such method is very inconvenient and introduces many possible errors, all of which may be avoided by direct viewing and focusing through the objective itself. The primary object of the present invention is the provision of a viewing device mounted upon a base'which may be inserted into the magazine chamber of the apparatus and which includes an optical system brought into operative relation to the photographic objective when the device is so inserted.

Another object of the invention is the provision of a viewing device including an optical system and a ground glass screen therein and also including a base member for supporting said optical system within the magazine chamber of the apparatus and in operative relation to the photographic objective with said ground glass surface in the focal plane ofthe objective.

Another object of the invention is the provision of awiewing device comprising a base member having an abutment for engaging and blocking an operating mechanism of the photographic apparatus stop the shutter thereof in open position.

Other objects of the invention will be apparent 40 to those skilled in the art from the disclosure which follows.

The above and other objects of the invention are'realized in a viewing device having a base member arranged to correspond to or simulate the outline of a film magazine, including an optical system mounted on said base member and having a ground glass focusing surface which is brought into the focal plane of the objective when the viewing device is inserted into the magazine chamber of the apparatus. Said base member also has locating surfaces for engaging the locating members in the apparatus, which normally support the film magazine in proper position, and has an abutment located to engage and block the co film advancing mechanism of the apparatus with the shutter member thereof in open position; Finally, the viewing device includes a releasing member for disengaging interlocking mechanism of the apparatus for its abnormal operation.

Reference is hereby made to the accompanying 5 drawings, wherein similar reference characters designate similar elements and wherein:

Fig. 1 is a transverse cross section through a photographic apparatus and the viewing device inserted therein.

Fig. 2 is a side elevation of the photographic apparatus showing the conventional elements thereof with which the viewing device of the invention co-operates.

Fig. 3 is a vertical cross section through the 15 assembled photographic apparatus and viewing device.

Fig. 4 is a front elevation of the viewing device.

Fig. 5 is a fragmentary elevation of the photo- 20 graphic apparatus particularly showing the manner of releasing the catch means of the apparatus to permit unlocking of the latching means for the cover of the apparatus.

Fig. 6 is a fragmentary perspective oftherear 25 of the viewing device and of the film advancing mechanism of the apparatus for illustrating the blocking action of the abutment on the viewing device.

Fig. '7 is a perspective of the complete viewing 30 device from the front.

The present invention is to be explained in connection with a standard motion picture apparatus ofthe magazine type but'it is to be understood that the viewing device of the invention may also 35 be applied to the other forms of photographic apparatus of the magazine type.

The photographic apparatus or motion picture camera of the illustrated embodiment is enclosed within a casing ill having a side wall H, a front 40 lateral wall l2, a top lateral wall l3, a rear lateral wall l4 and a bottom lateral wall IE to which a flanged cover I6 is connected by hinges l1, said lateral walls I2, II, M and I5 being provided with an undercut recess l8 for light-sealing engage- 45 ment with .the flange of cover It.

An objective socket I! is mounted within casing l0 adjacent front lateral wall I2 and receives and supports the objective assembly or photographic objective 2!. vided in the rear end thereof with an exposure, aperture 2!. I I

A main mechanism plate 22 is mounted within casing Ill adjacent but in spaced relation to side wall H. A cover plate 23 is mounted in parallel Said objective socket is pro- I within the apparatus. A front plate 24, see Figs.

-hinge 31 into winding position.

1 and 2, is mounted perpendicularly to cover plate 23 to form the front wall of the e chamher and is'provided with an exposure aperture in registration with the exposure aperture 2| in the objective socket l3. A supporting block II is mounted along the bottom lateral wall Ii and includes locating members 21 for engaging and podtioning the film magazine within the e chamber. The cover plate 23 has a plurality of integral bosses 23 and carries a pair of springs 23. A spring 23' is mounted on the objective socket l9 and acts in conjunction with the other springs and locating members accurately to position the fllm magazine when it is inserted into the magazine chamber. The magazine chamber is defined by cover plate 23, flanged cover I, front plate 24, a portion of .top lateral wall l3, a portion .of rear lateral wall I and supporting block 26.

The operating mechanism of the photographic apparatus will next be described and includes a prime mover, a shutter member, film advancing mechanism, and interconnecting gear trains. The prime mover is preferably provided as a pair of spring motors 30, each motor comprising a casing 3| fastened to the main mechanism plate 22 and containing a coil spring 32 which has its outer end attached to casing 3| and its inner end attached to an arbor 33. Said arbor 33 extends through mechanism plate 22 and carries a pinion gear 34. Said spring members 33 may be wound in conventional manner such as by a crank 35 having a handle 36 and connected by a hinge 31 to a collar 38 surrounding a winding shaft 39. Said winding shaft 39 has a square outer end adapted to be engaged by the square aperture 4| in crank when said crank 35 is swimg about A gear 42 is mounted on winding shaft 39 and meshes with a gear 43 which in turn meshes with the two pinion gears 33. Said gear 43 is mounted on a shaft 43 which extends through main mechanism plate 22 and is journaled at its other end in cover plate 23.5 It will be understood by those skilled in the art that rotation of winding shaft 33 will wind the spring motors 33 to store potential energy therein and that said spring motors 33 will give up such energy by rotating pinion gears 34 and shaft 43. V

The driving power from the spring, motors 33 is conducted to the various other elements of the operaitng mechanism from shaft 44 by a a pinion gear 43 which meshes with a small gear 46 mounted upon a shaft 41; Atake-up clutch member 43 is mounted on the end of shaft"- and extends into the e chamber for engagement-with a complementary clutch member Shaft 41 also carries a pinion gear 43 in mesh with a pinion gear 53 mounted on a shaft 5| joumaled between mechanism plates 22 and 23.'

The shutter member of the operating mechanism comprisesa conical shutter 52 provided with an opening 53 and mounted upon a shaft 34, which is rotatably mounted at'one end upon a portion of the objective socket II, and which carries at its other end a beveled gear 35 meshing with a beveled gear on a shaft 31 lownaled in cover plate 23-andcarrying a gear 51' 4 which meshes with the pinion gear 33- Conse-' quently, rotation of pinion gear 33 will cause rou tatlon of the conical shutter 32 which normally covers exposure apertures 2| and 25 but which intermittently uncovers the same when the shutter opening 53 registers with said apertures 2| and 23.

The operating mechanism also includes a film advancing mechanism which comprises a flimengaging member or claw arm 53 having at one end a head 53 and being eccentrically connected at the other end to a disc 63 which is mounted upon a shaft 6| journaled between the mechanism plates 22 and 23. The gear 62 on shaft 3| meshes with gear so that upon rotation thereof the claw arm 53 is reciprocated for intermittent engagement with and advancement of the film in the film magazine within the. magazine chamber. advancing mechanism are directly geared together, they operate in a known manner in timed relation so that the film is advanced only during closed positions of the conical shutter.

A control means, also of conventional design, is arranged to engage and stop the aforementioned operating mechanism. Such a control means comprises a single toothed cam 63 mounted on shaft BI and a blocking member 64 slidably mounted by pins 65 on the main mechanism plate 22 and operated from the exterior of the apparatus by a finger lever 66 mounted on the outer end of a shaft 61 which also carries on its inner end a connector' engaging a. jaw 69 provided in blocking member 65 A projection 10 extends from blocking member 64 for engagement with the single toothed cam 63. Hence, upon operation of finger lever 86' the shaft 61 and connector 63 are rotated to raise the blocking member 63 along. pins 65 and to disengage projection Hi from the single toothed cam 63 so that the spring motors 30 are free to operate the shutter member and film advancing mechanism of the apparatus.

It is quite desirable to provide an interlocking arrangement so that the apparatus cannot be operated when its cover is open or when there is no film magazine or equivalent apparatus in the magazine chamber. To this end the latching means for the cover Ii has a projection for blocking the aforementioned control means and said latching means is normally maintained in unlocking position by a catch means. The latching means'comprises a bar H slidably mounted along the inner surface of the top lateral wall 13 and operated by an external finger piece I2. Said bar II' has a longitudinal flange 13, see Figs. 2 and 3, for engaging a hook member 14 on the inside of cover I i when the finger piece 12, bar II and flange 13 are moved into locking position indicated by the dotted lines in Fig. 2. vIn the unlocking position of the latching means which includes bar H, finger piece I2 and flange 13, shown by the full lines in Fig. 2, the flange I3 is disengaged from book member II and the cover I may be opened. The bar II also carries a saddle member 15 for engaging the shutter pin on the fllm magazine, not shown. The slidable bar II is provided at one end with a projection l3 whichis in the plane of movement of the blocking member 34 and which, in the pofltion shown in Fig. 2, prevents movement of the control means and blocking member I to a disengaging position. The blocking member 64 also carries an arm 11 so that the control means Since the shutter member and film is blocked against operation until the latching 4 means including finger piece I2 and bar H are moved to locking position.

The latching means is held in unlocking position by a catch meanswhich includes a U-shaped spring I8 provided with a central opening, not shown, into which a tooth 19 on the bar 'II may extend. Said spring 18 is disengaged by a tapered pin, not shown, on the cover I8. The arrangement of the control means, latching means and catch means is similar to that illustrated and described in .Wittel U. S. Batent No. 2,080,- 021, issued May 11, 1937, and the entire camera mechanism thus far described is known to the prior art.

The viewing device of the invention comprises a base member carrying an optical system equipped with a ground glass screen which upon insertion of the viewing device into the apparatus is'located in the focal plane of the objective.

The base member of the viewing device comprises a frame member 88 having a central channel formed by the side walls 8|. Said frame member 88 also includes a pair of front oppositely extending projections 82 each having a locating surface 83 and also includes a pair of oppositely extending rear projections 84 each having a'locating surface 85. The rear surface of the frame member 88 may be hollowed out to reduce the weight of the viewing device but posts 88 extend from the frame member and are located so as to engage the bosses 28 on the cover plate 23, see Figs. 1, 3 and 6. I

The optical system of the viewing device includes a positive lens 81 having a ground plano surface 88, a pair of mirrors 89 for directing the image through a displaced path and through a lens 98 which is mounted in a carriage 9|, and includes a diaphragm member 92 carrying the front ocular element 93, the rear ocular element 94 being mounted at the rear endof the channel in the base member of the viewing device. A cover plate 95 encloses the channel in the base member and includes a front plate 98 provided with an exposure aperture 91 and a locating member 98. The aforementioned carriage 9I is slidably mounted on cover plate 95 by means of a finger piece 9| so that the lens 98 may be moved between conjugate focal positions. In the rear position of the lens 98 the field covered by the objective of the camera will be indicated at a relatively low magnification, while in the forward position of lens 98 only a portion of the field will be observed but such portion will be at high magnification for greater accuracy in focusing of the objective 28.

The base member of the viewing device is formed so as to equal or correspond to the outline of the film magazine ordinarily used in the apparatus and said base member will be positioned within the apparatus by the locating members which ordinarily position the film magazine.

In other words, the locating surfaces on the viewing device are engaged, positioned and supported by the various locatingvmembers of the apparatus so that the viewing device is positioned just as accurately as the film magazine is positioned. -By the same token the ground glass surface 88 on positive lens 81 is located in the focal plane of the objective 28 justas accurately as the film in the magazine is located in that focal plane.

However, in the ordinaryphotographic apparatus of the motion pi'cti'ufe type the shutter is in closed position wheri'the control means becomes operative to stop the apparatus. The' viewing device of this invention is particularly adapted to remove'the obstacles to such stopping of the shutter in closed position so that the spring motor of the apparatus can act to open the shutter.

Accordingly, a releasing member is detachably mounted in the viewing device and specifically comprises a tapered pin 99, a threaded portion I88 and a knurledportion IN. A flexible chain I82 is fastened at one end to knurled portion IN and at the other end to the frame member 88. A portion of the front projection 82 is bored and threaded to receive the pin 99 and threaded portion I88 of the releasing member. Said releasing member may be detached from the frame member of the viewing device and inserted between the legs of the U-shaped spring I8 for movement of the spring to disengage the tooth to locking position so that the control means for 1 the operating mechanism may be disengaged.

In addition to the release of the control means there must also be some arrangement for blocking the operating mechanism with the shutter member in open position. According to the present invention, the wer front projection 82 of the base member is provided with a recess I83 which is opposite the claw arm 58 of the film advancing mechanism and which terminates in an abutment I84 located and arranged so as to block the claw head 59 and to stop the operating mechanism when the opening 53 of the shutter 52 is in registry with the exposure apertures 2I Since the viewing device 00-- and 25 in the objective socket I9 and front plate 24, respectively. The relative positions of the claw head 59 and the abutment I 84 during the normal stopped position of the apparatus are indicated by the dotted lines in Fig. 6, while the angular movement of the disc 88 through the angle alpha and linear movement of the claw arm 58 with claw head 59 abutting against the abutment I84 is shown by the full lines in Fig. 6. As a result, after insertion of the viewing device in the magazine chamber and release of the catch means to permit movement of the latching means to locking position and disengagement of the control means, the spring motors operate. through. the intervening gear trains to move the film advancing mechanism and claw arm 58 until the claw head 58 abuts against abutment I84 at which time the shutter opening .53 is opposite the expo-- sure apertures 2| and 25. This makes the photographic objective 28 available so that by sighting through the rear ocular 94 the field covered by the objective 28 is indicated when the lens 98 is in the rearward position and a portion of the field may be observed at greater magnification when the lens and its carriage 9| are moved to the forward position. In such forward position the objective 28 may be focused with simultaneous observation of the image on the ground glass surface 88. By reason of such'increased magnification this focusing operation may be conducted very accurately.

As previously pointed out,- the present disclo- -sure is to be considered only in an illustrative sense and the scope of the invention is defined in the appended claims.

Having now particularly described my inven- N tion what I desire to secure by Letters Patent the United States and whatI claim is:

I. In a photographic apparatus, the combination with a casing carrying an objective and provided with a chamber for a film carrier, a shutter member movable into a closed,.position and into an open position respectively to intercept andto permit the passage of light from said objective to said chamber, an operating mechanism connected to said shutter member and including a prime mover for driving the same, and a control means for engaging said operating mechanism and for stopping the same with said shutter member in closed position, of a viewing device including an optical system and adapted to be inserted into said chamber with said optical system in operative relation to said objective, and having a portion arranged to engage said operating mechanism, upon disengagement of said control means and movement of the shutter by said prime mover, and located to stop said operating mechanism with said shutter in its open position.

2. In a photographic apparatus, the combination with a casing carrying an objective and provviewing device including an optical system and I adapted to be inserted into said chamber with said optical system in-ope rative relation to said objective-and having a portion arranged to engage said gim-engaging-member, when said control means is. disengaged for movement of said film engaging member and said. shutter by the spring motor; and located to stop said film engagingmember withsaid shutter in its open position.

3. In a photographic apparatus, the combination with a'casing carrying an objective and provided with a magazine chamber, a cover for said. casing, a shutter member'movable into closed and open positions, an operating mechanism connected to said shutter member and including a spring motor for driving the same, a control means arranged to engage saidv operating mechanism and to stop the same with said shutter member in closed position, a latching means movable to locking and unlocking podtions, for fastening in said locking position said cover to said casing and including a portion which in unlocking position of said latching means engages and blocks 'said' controlmeans in engaged position, and a means.

4. In a photographic apparatus, the combination with a casing carrying an objective and pro- ;vided with a chamber for a film carrier, a cover for said casing, a shutter member movable into closed and open positions, an operating mechanism connected to said shutter member and including a spring motor for driving the same, a control means arranged to engage said operating mechanism and to stop the same with said shutter member in closed position, a latching means movable to locking and unlocking positions, for

fastening said cover to said casing in said locking position and including a portion which in unlocking position of said latching means engages and blocks said control means in engaged position, and a catch means located and arranged releasably to engage and hold said latching means in unlocking position, of a viewing device comprising a base member adapted to be inserted into said chamber, an optical system on said base member and inoperative relation to said objective when said base member is inserted into said chamber, a releasing member mounted on said base member and movable to engage and release said catch means for permitting movement of said latching means to locking position and disengage-r ment of said control means, and a portion on said base member arranged to engage said operating mechanism upon ement of said control means and located to stop said operating mecha 5o nism with said shutter in its open position.

Domino L. woon. 

